Sixteen spotlight counts were conducted at night between June and August 1998 in an area with a high density of sika deer (Cervus nippon) in Nikko National Park, Japan. Behavioral responses to spotlights were analyzed, and distance sampling techniques (DST) were used to estimate deer den-sity. Deer behavior at the time of sighting and subsequent behavioral responses to spotlighting were recorded. Deer with perpendicular distance ≤ 5 m from the census route showed a flight ratio of 6.3% at the time of sighting, but deer > 5 m showed little flight response. Deer ≤ 5 m showed a relatively high flight response of 4.1-22.2% during census events, while deer further than 15 m exhibited a low flight response. Our results show that the spotlight count method meets the basic theoretical assumptions of the DST.

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Nine female sika deer Cervus nippon were tracked by radio telemetry in eastern Hokkaido in the summer of 2000. Two habitat use sampling techniques were then compared: diurnal location sampling (diurnal sampling) and sampling every 2 hours over 24 hour periods of tracking (24-hr sampling). Habitat use determined by diurnal sampling for eight sika deer was not different from that determined by 24-hr sampling, and habitat use by six sika deer did not differ between day and night in the 24-hr sampling events. This suggests that diurnal locations sufficiently represent the overall patterns of habitat use. Three sika deer tended to use relatively open habitats more frequently during the night than during the day, possibly to avoid human disturbances. Most of the nocturnal locations of eight deer were distributed within or overlapped with the home ranges estimated by diurnal sampling, while some nocturnal locations of one deer in agricultural fields were outside its diurnal home range. The use of agricultural fields may be underestimated by diurnal sampling alone.

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The upper dental formula of the Russian desman Desmana moschata (Linnaeus, 1758) (Insectivora, Talpidae) is considered based on the position of the premaxillary suture (sutura incisiva). From the lateral aspect, this suture extends to the second tooth in the tooth row. From the ventral aspect, the suture connects the common alveolus fossa of the second and third teeth in front of the second tooth on the labial edge and behind it on the lingual edge; consequently, the third tooth in the upper row appears to be derived from the maxilla. Therefore, the upper tooth formula of D. moschata may differ from the traditional fundamental dental formula of eutherian mammals (I3, C1, P4, M3), and consist of two incisors, one canine, five premolars, and three molars (I2, C1, P5, M3). This hypothetical view, however, assumes two changes, a tooth deletion in the incisor row and an addition in the premolar row. The significance of the premaxillary suture and possible pitfalls in using it to define dental formulae are discussed.

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Geographic variation of the mole-shrew, Anourosorex squamipes Milne-Edwards, 1872 (Mammalia: Insectivora: Soricidae) was examined on the basis of 18 cranial morphometric characters of 112 specimens collected from the provinces of Sichuan and Yunnan in China, and from northern Vietnam, Assam, and Taiwan by using univariate and multivariate statistics. The Assam sample was larger in overall dimensions than those from Sichuan, Yunnan, Vietnam, and Taiwan. The Taiwan sample differed from other samples in its proportions. Three allopatric forms were recognized and assigned subspecific status: populations of Sichuan, Yunnan, Vietnam, Myanmar, and Thailand were assigned to A.s. squamipes; populations in Assam south of the Bramaputra River were assigned to A.s. assamensis Anderson, 1875; and populations in Taiwan were assigned to A.s. yamashinai Kuroda, 1935. Anourosorex s. schmidi Petter, 1963 from Bomdila in Assam north of the Bramaputra River was tentatively retained as a fourth subspecies.

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The muscles of the forelimb were functional-morphologically examined in a carcass of the aardvark (Orycteropus afer) that is highly adapted to the fossorial life and the digging behavior. The M. pronator quadratus, the M. abductor digiti I longus, the M. brachioradialis, the M. pronator teres and the M. supinator are well-developed. We suggest that the supinator-pronator movement by these muscles enables the aardvark to dig, crush and sweep the soils in its fossorial behavior. In addition, the M. extensor digiti II runs obliquely to rotate the forearm around the ulna shaft. We think that this muscle may not only function as an extensor of the digits II and III, but also as a supinator of the fore arm. Many extensor muscles can be separated into two groups on the basis of their insertion. The M. extensor digiti II and the M. extensor carpi radialis insert to the digits-metacarpals II-III, whereas the M. extensor digitorum lateralis and M. extensor carpi ulnaris reach the digits-metacarpals IV-V. We suggest that the crushing of the soil is accomplished by the two medial digits and that the lateral two digits mainly act as a remover or a sweeper of the crushed soil.

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Because feral American mink are a successful alien carnivore worldwide, demands for field studies are likely to grow. Appropriate methods for trapping, use of anaesthesia, handling and radio-tracking are important from both academic and animal welfare view points. From accumulated field studies of mink over the last 30 years, including our own, we describe the problems that researchers will likely face in the field, and offer possible solutions for them. Surveys in the breeding and kit dispersal seasons likely inflate the estimated populations, and the best time to assess a local mink population is kit rearing season (May to July in the UK). The best trapping sites occur in the junction between a hedge/ditch and waterside cover. A mass of dry hay, with which the traps are wrapped, prevents mink from damaging their teeth. In the field mink is safely anaesthetised using a combination of a volatile agent (isoflurane), and injectable agents (medetomidine and ketamine mixture), which produces anaesthesia lasting for 60 minutes or more, and is reversible with another injectable agent (atipamezole). In lowland England triangulation is not necessary to locate animals by radio-tracking although obtaining radio signals is problematic when animals are under ground.

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